Nowadays, spam calls have become a public nuisance. In order to prevent such calls, many security products emerge. For example, when a user receives a spam special software may assign a tag such as “telemarketing”, “fraud” and the like to the incoming call, and the tag is uploaded to a cloud end server. When other users receive calls from the same number, the tag may be shown to them to filter such calls.
However, filtering by tags does not apply to all situations in practice, and thus it is important to improve the method to make it more applicable.